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NEMA 14-50 is dead - all hail NEMA 6-50

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So this may seem a bit controversial, but now that Tesla is no longer shipping the 14-50 adapters with the UMC / new vehicles, I would like to throw out there that 14-50 is perhaps no longer the logical receptacle to install for home installations.

Here are the benefits of a 6-50 receptacle over a 14-50:
  • Does not require a neutral wire which is an added cost
  • Cable is smaller in diameter and more flexible, so easier to install
  • Receptacle is less expensive
  • Less wires required in the wall box makes for easier installation
Here are the downsides of a 6-50 over a 14-50:
  • Future EVSEs might not come with a 6-50 receptacle option (though there are J1772 EVSE's that support 6-50 right now)
  • You can't use the receptacle for visiting RV's (most EV owners won't care about this)
  • Buying the 14-50 adapter from Tesla instead of the 6-50 would allow you to use that 14-50 adapter elsewhere when on the road (and 14-50 is more common these days than 6-50)
Here is a back-of-the-napkin example of a basic installation cost comparison:

Screen Shot 2019-05-04 at 8.33.30 AM.png


Now this assumes basic 6 gauge copper NM cable and at 100 feet (which perhaps is a little longer than the average install?)

The 14-50 comes out to be almost 62% more expensive!

Now, if you are paying a professional to install this, the vast majority of the cost is probably their labor and the delta cost for them to do a 14-50 vs. a 6-50 is not much (6-50 is going to be less stiff so perhaps marginally easier to install).

Am I missing anything here?

What do you think?
 
I don’t think the ubiquitous 14-50 is going anywhere, but you have a great point about the installation cost of a 6-50. Perhaps it will become more common for home Tesla charging. Clipper Creek makes some J1772 EVSEs with the 6-50 plug.
 
Here are the downsides of a 6-50 over a 14-50:
  • Future EVSEs might not come with a 6-50 receptacle option (though there are J1772 EVSE's that support 6-50 right now)
  • You can't use the receptacle for visiting RV's (most EV owners won't care about this)
  • Buying the 14-50 adapter from Tesla instead of the 6-50 would allow you to use that 14-50 adapter elsewhere when on the road (and 14-50 is more common these days than 6-50)
That one is pretty much negated since you can buy a separate 14-50 adapter from the savings and still have money left over. ;) I think you have a good point about the 6-50.
 
Not changing things at all. A 6-50 isn't a great option to install, I tend to question your numbers a little, but it's the flexibility of the 14-50 that's important. That's what other EVs use and what larger motorhomes use . It's easy to convert the 14-50 to anything else, because it has the ground and neutral wire . It's just a more flexible solution.
You just paid over$40k, is $100 a big deal? Also, the plug, as mine has, will out last a car, maybe out last 5 cars. Much cheaper to get it right the first time.
 
If you're going to put in a plug, the 14-50 is way more versatile and found in every camp site around the US. In our case, the EVSE is like 8 feet from our power box, so cable cost difference is negligible. The ease of installation of 4 vs 3 wires is negligible: literally one extra screw to loosen/tighten on each end. Overall I think you're splitting hairs except for the situation where you've got a very long run and a tight budget.
 
If you're going to put in a plug, the 14-50 is way more versatile
That's one way to view it. The other is that the 6-50 is really a better match for EV charging, since no EVSE will ever have mixed 120/240V loads. So unless you plan to use the outlet for something else (e.g. feeding an RV in case the outlet is outside) you're probably wasting money on a 14-50.
 
I would like to throw out there that 14-50 is perhaps no longer the logical receptacle to install for home installations.
What do you think?
Ok, the Tesla UMC doesn't use Neutral, however:

- Unless it's a DIY "Do it yourself" project, saving $83 for 100 feet long by not installing a Neutral wire is meaning less.
Typical Labor for this type of job by an electrician could be in the $2k - $5k range.

- Corrected web link for the above quote: Copper Building Wire (Thank you for the useful link)

- The NEMA 14-50 is the current norm: i.e. new oven-range, typically using the (now deprecated) 10-30, include a 14-50 instead.

Few years from now you might get a new EV charger, or want to instal a 120 V plug when the charger is not used...

Note: The 6-50 was designed typically to be used with a 6-gauge flexible power cord up to 200 ft,
thus not having a Neutral was understandable for more practicability.
 
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This is kind of an interesting discussion, when did they stop shipping the 14-50 adapters with new cars? I took delivery on 4/16, and mine came with one.

The outlet cost appears to be widely variable, but they certainly can be had for less than that. I believe I paid $7.86 at my local home improvement store for my 14-50 outlet. The three wire cable is more expensive for sure, but beyond that I don't see much of an advantage of the 6-50. The Mobile Connector certainly checks for that neutral circuit, though… When testing the wiring my neutral slipped off in the breaker box and the indicator on the Connector turned red and stopped charging. It may not use it, but it certainly wants it to be there for some reason.
 
This is kind of an interesting discussion, when did they stop shipping the 14-50 adapters with new cars? I took delivery on 4/16, and mine came with one.

The outlet cost appears to be widely variable, but they certainly can be had for less than that. I believe I paid $7.86 at my local home improvement store for my 14-50 outlet. The three wire cable is more expensive for sure, but beyond that I don't see much of an advantage of the 6-50. The Mobile Connector certainly checks for that neutral circuit, though… When testing the wiring my neutral slipped off in the breaker box and the indicator on the Connector turned red and stopped charging. It may not use it, but it certainly wants it to be there for some reason.

They stopped in recent weeks. Depending on when your car was produced it may or may not have both in it (hit or miss while they still have inventory in the pipe).

The really inexpensive receptacles you are quoting are likely Leviton from Home Depot. They are not recommended to be used (by Tesla). There is a thread around here somewhere where someone ordered one of each brand and compared them. The Leviton one was absolutely the most flimsy. We have seen a number of them melt on the forums here.

So it seemed like the best bang for your buck (quality vs. price wise) was the Bryant ones. So here are the ones I used as my examples:

Bryant 50A Single Receptacle 250VAC 6-50R BK 9650FR | Zoro.com
Bryant 50A 4W Single Receptacle 125/250VAC 14-50R BK 9450FR | Zoro.com

The mobile connector for sure does not check anything to do with the neutral pin. You can cut them off your UMC on the 14-50 adapter and it still works fine. I have an extension cord that literally has no neutral wire in it and it works. I suspect the scenario you describe is that somehow neutral and ground were not properly bonded together in your electrical system (scary!) or your ground connection was loose (not neutral). If using a 10-30 receptacle the UMC does use the neutral wire as a ground, so that could explain it too.
 
So this may seem a bit controversial, but now that Tesla is no longer shipping the 14-50 adapters with the UMC / new vehicles, I would like to throw out there that 14-50 is perhaps no longer the logical receptacle to install for home installations.

Here are the benefits of a 6-50 receptacle over a 14-50:
  • Does not require a neutral wire which is an added cost
  • Cable is smaller in diameter and more flexible, so easier to install
  • Receptacle is less expensive
  • Less wires required in the wall box makes for easier installation
Here are the downsides of a 6-50 over a 14-50:
  • Future EVSEs might not come with a 6-50 receptacle option (though there are J1772 EVSE's that support 6-50 right now)
  • You can't use the receptacle for visiting RV's (most EV owners won't care about this)
  • Buying the 14-50 adapter from Tesla instead of the 6-50 would allow you to use that 14-50 adapter elsewhere when on the road (and 14-50 is more common these days than 6-50)
Here is a back-of-the-napkin example of a basic installation cost comparison:

View attachment 404018

Now this assumes basic 6 gauge copper NM cable and at 100 feet (which perhaps is a little longer than the average install?)

The 14-50 comes out to be almost 62% more expensive!

Now, if you are paying a professional to install this, the vast majority of the cost is probably their labor and the delta cost for them to do a 14-50 vs. a 6-50 is not much (6-50 is going to be less stiff so perhaps marginally easier to install).

Am I missing anything here?

What do you think?
Weird decision. I would assume it’s to cut cost more so than to save us buyers money on the install. Bean counting as the experts say
 
  • Informative
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